Add GHA workflow to run tests

Author: ErikSchierboom

.github/workflows/ci.yml

@@ -0,0 +1,17 @@
+name: CI
+
+on: [push, pull_request]
+
+jobs:
+  test:
+    name: Run tests
+    strategy:
+      matrix:
+        os: [ubuntu-latest, windows-latest, macos-latest]
+    runs-on: ${{ matrix.os }}
+    steps:
+      - uses: actions/checkout@5a4ac9002d0be2fb38bd78e4b4dbde5606d7042f # 2.3.4
+      - uses: actions/setup-dotnet@a71d1eb2c86af85faa8c772c03fb365e377e45ea # 1.8.0
+        with:
+          dotnet-version: 5.0.202
+      - run: dotnet test